Although I don't think your original question was directly asking this - the PathPilot install disc doesn't actually "install" Linux. It deploys a disk image that already has Ubuntu + realtime kernel + PathPilot setup and configured.

It was mentioned above, but there is nothing to "jailbreak" in PathPilot. It literally is an Ubuntu 10 LTS distro with a user called "operator" that has some LinuxCNC configuration files in their home directory. These LCNC config files, when combined with a few scripts and utility binaries makeup PathPilot.

You can launch a command prompt with ctrl+alt+x once PathPilot is up and running, sudo -i to root and do whatever you please with the underlying OS. Do keep in mind that Tormach is trying to create an "appliance" with this distro, hence the reason it auto boots into the operator account, closes the x-window manager and launches LCNC with the correct PathPilot configuration. Running it this way will give the most reliable and stable results.

Note: If you do edit the configuration, make sure to backup your files to use a CM tool to control your changes, because a PathPilot update will overwrite the top-level config file and create a brand-new subdir for PathPilot with every release.

Best of luck!